Amazon set out to do something different with the unveiling of its first smartphone on Wednesday. How about a completely new way of interacting with your phone, for starters?

As part of the showcase of its brand new ''Fire Phone,'' Amazon.com Inc. took the wraps off a feature it calls ''dynamic perspective.'' Turns out, it's more than just a gimmick that allows you to see in 3-D.

The feature makes use of four infrared cameras pointed at your face that help judge whether you're looking at the screen straight-on, at an angle and how close you are to the screen. The phone can then adjust the image accordingly. That gives you the ability to see depth in images, to see around objects in the foreground, to zoom in for a better look, and to toggle through websites, books and menus and even to play games by tilting the phone back and forth and up and down while you look at it.

Another feature called ''Firefly'' brings what's known as augmented reality to life in a new way, by turning your phone into a powerful tool that recognizes book covers, CDs, DVDs, songs, movies, grocery items, phone numbers and websites and pulls them into the phone so you can take action.

For Amazon, the major benefit of this is that it takes price comparison shopping to a new level, because any item you see while walking down the aisle of a Walmart or Target can get an instant price check. Amazon says the phone can recognize more than a hundred million items. And if you link your credit card information to the service, you can make a purchase with a couple taps.

But more than that, by releasing these tools to developers, Amazon has made what could be a major contribution to what a smartphone can do.

With about a half hour to try out these features and have them explained in depth, I was both impressed and saw some flaws.

The 3-D effect is quite stunning. Just imagine looking down a long hallway and putting your ear against each wall one after the other. Your perspective changes and straight lines will seem to disappear to a different point. To demonstrate the effect on the phone, Amazon made available a bunch of lock-screen images, like the cartoon ruins of a pyramid, some hot-air balloons and a jungle setting. Swiveling the phone